Using oxide junction to cut off sub-threshold leakage in cmos devices

Abstract

A new method is provided for the formation of Lightly Doped Drain (LDD) regions in MOS devices. The body of the gate electrode is formed including the self-aligned LDD regions. After the LDD regions have been formed, an oxide implant is performed under an angle into the surface of the substrate on which the MOS device is being formed. This oxide implant forms an oxide layer around the interface between the source/drain regions and the surrounding silicon. The spacers for the gate electrode are formed, the source/drain region implant is completed. This implanted oxygen junction is subjected to a thermal treatment thereby forming an oxide layer around the source/drain regions. This oxide layer eliminates the leakage current across the interface between the source/drain regions and the surrounding silicon further forcing the saturation current between these regions to flow along the surface of the silicon substrate.